RFR: JDK-8305484: Compiler::init_c1_runtime unnecessarily uses an Arena that lives for the lifetime of the process

[Justin King]

Remove unnecessary usage of Arena for globals that live the lifetime of the process and are initialized once.

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Commit messages:
 - Remove unnecessary use of an Arena in C1

Changes: https://git.openjdk.org/jdk/pull/13300/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=13300&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8305484
  Stats: 50 lines in 5 files changed: 20 ins; 9 del; 21 mod
  Patch: https://git.openjdk.org/jdk/pull/13300.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/13300/head:pull/13300

PR: https://git.openjdk.org/jdk/pull/13300